All search engines currently used on the Web, such as Google, Yahoo, Youtube, and many other domestic search engines, are text-based. Even though each of aforementioned search engines is dedicated to break the limit of text-based search, for example, by hunting contents containing the keyword in both traditional Chinese and simplified Chinese (or even in other languages), the search result is still limited by the keyword. For example, when related multimedia data (audio or video files) is to be searched, it may not be possible to find the correct data or enough related data by using the keyword because of insufficient text content in the keyword or different translations of the keyword adopted by different countries.
The search engine Google started to offer an image search service since April, 2009, and this is the first service in the world which allows a user to search for related data according to an image content. For example, referring to FIG. 1A, when a keyword 110 (“apple”) is input in the input field 120, data related to “apple” is displayed. Herein the related data includes all images containing an apple-shaped object and the cell phone (“iPhone”) with the trademark “Apple®”. Unwanted data can then be eliminated by performing further selections. For example, as shown in FIG. 1B, after a user selects an image containing an apple-shaped object, the search engine further displays images related to this fruit (apple). Or, as shown in FIG. 1C, after the user selects the image of “iPhone” with the trademark “Apple®”, the search engine displays other images related to this product to allow the user to find the desired image. However, this technique is to look for images based on an image content, and which is limited to the search of related image files and does not work on multimedia files.
In order to resolve aforementioned problem, a standard for providing complementary data of a content (in particular, a digital multimedia content) is described in the MPEG-7 protocol established by the Motion Picture Expert Group (MPEG). According to this MPEG-7 standard, a corresponding multimedia content description independent of other MPEG standards is provided to a multimedia content, and the digital content description may even be attached to an analog movie file. A corresponding content description is provided to each audio-visual content, wherein the content description describes related characteristic values of the audio-visual content, and which is arranged in a file as:AV+Descript+AV+Desript+AV+Desript+ . . .
Herein “AV” represents the audio-visual content, and “Descript” represents the corresponding content description.
However, such a structure is very complicated and requires all multimedia files to be re-arranged therefore is not applicable to existing files and structures. Besides, even though related multimedia files can be located through keyword search by using the characteristic values, the technique is still limited by the text-based search with respect to different languages.
Additionally, inputting keywords on TV to search videos is unavoidable with the ongoing trend of Internet TV. How to accomplish a video search function on Internet TV by using remote control is one of the major subjects in the development of such applications.